Western Wind and Solar Integration Study

Western Wind and Solar Integration Study Final Report

May 20, 2010

The Western Wind and Solar Integration Study (WWSIS) (PDF 20.6 MB) Download Adobe Reader investigates the
operational impact of up to 35% energy penetration of wind, photovoltaics (PVs), and
concentrating solar power (CSP) on the power system operated by the WestConnect group
of utilities in Arizona, Colorado, Nevada, New Mexico, and Wyoming.

The Western Wind and Solar Integration Study and its sister study, the Eastern Wind Integration and Transmission Study (EWITS), follow the U.S. Department of Energy's (DOE) 20% Wind Energy by 2030 Study that considered the benefits,
costs, and challenges associated with sourcing 20% of the nation's energy from wind power by 2030. The study found that while proactive measures were required,
no insurmountable barriers to reaching 20% wind were identified. Thus, DOE and the National Renewable Energy
Laboratory (NREL) embarked upon WWSIS and EWITS to examine, in much greater depth, whether there were technical or physical barriers in operating the grid with
20% wind. Solar power was included in WWSIS due to the significant solar resources and solar development in the West.

The technical analysis performed in this study shows that it is operationally feasible for WestConnect to accommodate
30% wind and 5% solar energy penetration, assuming that changes to current practice could be made over time.

The study was designed to answer questions that utilities, Public Utility
Commissions, developers, and regional planning organizations had about renewable
energy use in the West.